Flexible cable drive



July 20, 1965 M. E. SIMMONS 3,195,823

FLEXIBLE CABLE DRIVE Filed March 12, 1965 2 Sheets-Sheet 1 INVENTOR c5 ,3 HILTON z, smnous BY w za Hifi ATTORNEY July 20, 1965 M. E. SIMMONS FLEXIBLE CABLE DRIVE 2 Sheets-Sheet 2 Filed March 12, 1963 INVENTOR. MILTON E. SI NNONS HIS ATTORNEY United States Patent 3,195,823 FLEXELE CABLE DRIVE Milton E. Simmons, Rochester, N.Y., assignor to General Motors Corporation, Detroit, Mich, a corporation of Delaware Filed Mar. 12, 1963, Ser. No. 264,680 6 Claims. (Cl. 242-54) This invention pertains to flexible cable drive, and particularly to an improved mechanism for extending and retracting an elongate flexible actuating member which is coiled for storage within the mechanism.

Heretofore, various types of reeling and unreeling mechanisms for elongate flexible driving members have been devised for extending and retracting vehicle radio antennas having a plurality of relatively movable, telescopically arranged sections. For the most part the prior art drive mechanisms embody means to frictionally grip the flexible member, such as a cable, for reeling and unreeling the same to and from a storage chamber wherein a cable is coiled so as to adjust the antenna with which .retracting'a flexible cable; the further provision of driving means for extending and retracting an elongate flexible cable through deformation thereof; and the still further provision of an antenna actuator including a flexible cable drive embodying a chordal groove for reeling and unreeling the cable to and from its coil storage chamber.

The aforementioned and other objects are accomplished in the present invention by utilizing a drum having a substantially cylindrical portion upon which the cable is coiled, when retracted, the drum having an upstanding flange with a chordal or polygonal groove therein through which the cable extends and is deformed for reeling and unreeling the same from the cylindrical portion of the drum. Specifically, in the exemplary embodiment disclosed the improved cable driving mechanism is driven by .a reversible electric motor, one end of the cable being attached to the innermost section of the antenna structure. The cable is composed of a flexible plastic, such as nylon, and when the antenna is fully retracted, the major portion thereof is coiled on the drum within a storage chamber. Conversely, when the antenna is fully extended, the cable is uncoiled with the end portion thereof being situated in the chordal groove.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred embodiment of the present invention is clearly shown.

In the drawings:

FIGURE 1 depicts an electric motor driven radio antenna embodying the improved drive mechanism of this invention;-

FIGURE 2 is a side view, partly in section and partly in elevation, of the improved antenna actuator;

FIGURE 3 is a view, partly in section and partly in elevation, taken along line 33 of FIGURE 2;

FIGURE 4 is a sectional view taken along line 4-4 of FIGURE 2; and

FIGURE 5 is an enlarged fragmentary view depicting the deformation of the cable within the chordal groove of the drum.

With particular reference to FIGURES 1 and 2, the improved flexible cable drive means are depicted in combination with a vehicle antenna actuator comprising reversible direct-current motor having a gear reduction 3,195,823 Patented July 20, 1965 housing 12 and a storage housing 14 attached thereto. The gear reduction housing 12 and the storage housing 14 are connected to an outer support 17 of the antenna structure which includes a plurality of telescopically arranged adjustable sections 18. As seen more particularly in FIGURE 2, the motor 10 includes a rotary output shaft 20 having a pinion gear 22 on the end thereof in engagement with a spur gear 24 constituting the first gear redu tion stage. The spur gear 24 has an integral pinion gear 26 meshing with a spur gear 28 constituting the second reduction stage. The spur gear 28, in turn, has a gear 30 engaging an idler gear 32, the idler gear 32 engaging an internal gear 34 formed on a plastic drum 36.

The drum 36 is rotatably journalled by a flanged portion 38 of the storage housing 14, the storage housing 14 being attached to the gear reduction housing 12 by a plurality of bolts 40. A partition plate 42 is clamped between the storage housing 14 and the gear reduction housing 12, the partition plate 42, as seen more particularly in FIGURE 3, having entrance and exit ramp portions 43 and 44, respectively, in the form of helically inclined grooves spaced substantially 270 apart. As seen in FIGURE 4, the gear reduction housing 12 is formed with a substantially tangential passage 46 through which a flexible nylon cable 48 extends for attachment to the innermost antenna section.

The drum 36, as seen in FIGURES 2 and 4 is formed with a slightly tapered cylindrical portion 50 and an upstanding flange 52 having a chordal groove 54 therein. The cylindrical drum portion 50 is separated from the flange 52 by the partition plate 42 as clearly depicted in FIGURE 2. In the specifically disclosed embodiment the chordal groove is formed by twelve equiangular flats, the width of the groove 54 being greater than the diameter of cable 48. For example, when a .125 inch diameter nylon cable is used, the width of the chordal groove 54 may vary between .135 and .138 inches. It is to be understood that the number of flats can be varied and that the specific disclosure of twelve flats is only exemplary.

A portion of the cable is always situated within an angle of more than and less than 270 of the chordal groove 54. The cable 48, when situated in the chordal groove 54, is deformed in the manner depicted in FIG- URE 5. This deformation of the cable is suflicient to obtain the requisite thrust to both extend and retract the movable load device with which it is drivingly connected. It will be apparent to those skilled in the art that by increasing the number of flats for a given drum the thrust, or the driving force, will be increased, and vice versa. The end of the cable which is not attached to the movable load device is not attached to the drum 35, but when the cable is fully extended, this end portion must be situated within the chordal groove 54 or coiled within the storage chamber.

When the cable 48 is substantially fully retracted, the major portion thereof is coiled, or reeled, on the tapered cylindrical portion 50 of the drum in a helical fashion. A floating ring, or band, 56 is disposed within the storage chamber thus forming an outer bearing surface against which the convolutions of the coiled cable 48 come into contact. The ring 56 is free'to float axially as well as radially within the storage chamber, and thus serves to guide the cable 48 as it is being reeled or unreeled from this storage chamber to prevent buckling or misalignment of the convolutions.

Operation of the improved cable drive mechanism is believed to be self-evident in that upon rotation of the motor shaft 20 in one direction to extend the cable 48, the drum 36 will rotate so as to unreel the cable 48 from the storage chamber and extend it through the exit opening 46 in the gear reduction housing 12. Conversely, to

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CD a retract the cable 48, the motor'driven shaft 20 is rotated in the opposite direction thereby reeling, or coiling, the cable 48 on the drum portion 50 within the storage chamber.

While the embodiment of the present invention as'herej- I in disclosed constitutes a preferred form, it is to be under I stood that other forms might be adopted.

What is claimed is as follows: V

, a t 4 i Width of the chordal groove exceeds the thickness of said 7 g cable.

5. A flexible cable drive including, a coil storage chamber, an elongate flexible cable having one end connected with an object to be moved andfthe other end portion 7 coiled within said chamber, a drum having a substantially 1. A flexible cable drive including, a coil storage chain- 1 ber, an elongate flexible cable having one end connected with an object to be moved and the other end portion coiled Within said' chamber, arotatable deformation element adjacent saidchamber having a polygonal'surfacein driving engagement with said cable for coiling and uncoiling said cable insaidchamben-means separating said storage chamber from said rotatable element having helical ramp means therethrough for guidingsaid cable in its movement in either direction to ,andf rom said storage chamber; and meansioperable to rotate said deformation element.

2. A drive element for an elongate flexible cable comprising a drum having an upstanding flange with a polygonal groove therein, said cable being seated'within said,

groove for an angle of more than 180 but less than 360, 7 I

With the entrance and exit portions of said cableextending helically from said groove. 1

3. A drive element for an elongate flexible cable comprising a drum having an upstanding flange .vvitha chordal groove therein, said cable being situated in'said groove throughout an angle of more than 180 but less than 360? with the entranceand exit portions'of said cable extending helically therefrom. 1

i. The drive element set forth in claim 3 wherein the 7 cable is deformed in said chordal groove, and wherein the cylindrical portion disposed within said chamber upon which said cable is coiled and an upstanding flangewith a polygonal groovesadjacent' said chamberfor'receiving and deforming said cable to coil and uncoil said cable in said nected with an object to bet-moved and the other end portion coiled Within said chamben'a drive element adjacent said chamber having a chordalgroove for receiving and deforming said vcable. to coil and 'uncojil said cable in said chamber, means jseparating said storage chamber-from said rotatableielenient having helical ramp means therethrough forguidingsaid cablein its movement in either direction to and from said storage chamber; and means operable tojrotate said drive element.

l ljeferences Cited by the Examiner UNITED STATES PATENTS 2,623,175 12/52 Finke 242 54 '2,89 6,870 7759 Ulrich 242 s4 3,016,206 1/62 Cone 242-54 M RVINS EIN, Primary Examiner. 5 

1. A FLEXIBLE CABLE DRIVE INCLUDING, A COIL STORAGE CHAMBER, AN ELONGATE FLEXIBLE CABLE HAVING ONE END CONNECTED WITH AN OBJECT TO BE MOVED AND THE OTHER END PORTION COILED WITHIN SAID CHAMBER, A ROTATABLE DEFORMATION ELEMENT ADJACENT SAID CHAMBER HAVING A POLYGONAL SURFACE IN DRIVING ENGAGEMENT WITH SAID CABLE FOR COILING AND UNCOILING SAID CABLE IN SAID CHAMBER, MEANS SEPARATING SAID STORAGE CHAMBER FROM SAID ROTATABLE ELEMENT HAVING HELICAL RAMP MEANS THERETHROUGH FOR GUIDING SAID CABLE IN ITS MOVEMENT IN EITHER DIRECTION TO AND FROM SAID STORAGE CHAMBER; AND MEANS OPERABLE TO ROTATE SAID DEFORMATION ELEMENT. 